Control device for metallizing gun



May 9; 1 967 MINJOLLE CONTROL DEVICE FOR METALIZING GUN Filed Sept.

2 Sheets-Sheet 1 MIA/1041.5.

A-l'F' vmy y 1967 L. MINJOLLE 3,318,359

CONTROL DEVICE FOR METALIZING GUN Filed Sept. 2, 1965 2 Sheets-Sheet 2 United States Patent 87,54 12 Claims. (Cl. 158-125) ABSTRACT OF THE DISCLOSURE The control device provides means for automatic operation of metalizing guns and means to extinguish the gun in the event of some anomaly in its operation.

T he present invention relates to metalizing guns for example, for coating surfaces with sprayed metal, and more particularly to a device controlling the ignition and the extinction of said guns.

The object of the invention is to render automatic both the operation of the various processes involved when igniting the metalizing gun and the extinction of the latter in the event of some anomaly in the operation of the gun.

The invention provides a device controlling the ignition and the extinction of a metalizing gun including gas supply conduits supplying combustible gas, comburent gas and operating or projecting gas, and flow control means for controlling the flow through said gas supply conduits, said device comprising a jack fed with liquid from an exchanger connected to the gas supply conduit of the projecting gas, and in which the last-mentioned gas transmits its pressure to the actuating liquid, the jack being connected to said flow control means and to a device igniting the gun, whereby, under the action of the pressure of the gas supplied to the exchanger, it ignites the gun and upon a drop in the pressure in said gas below a given value, it extinguishes the gun.

Further features and advantages of the invention will be apparent from the ensuing description with reference to the accompanying drawings to which the invention is in no way limited.

In the drawings:

FIG. 1 is a diagrammatic view of one embodiment of the device according to the invention, and

FIG. 2 is a perspective view of a metalizing gun employing rods and comprising the device according to the invention.

With reference to the drawings, the illustrated metalizing gun is supported by a column 1 and comprises a device automatically feeding the rods generally indicated by the reference numeral 2. This device is of the type described in copending application No. 485,256 filed on Sept. 7, 1965, for Device for Automatically Feeding Blowpipes Employing Rods.

This device is mounted-in a casing 3 on which is fixed a housing 4 containing the devices (valves or taps) admitting the gases to the gun and the actuating device there- ,for. Fixed to this housing is a case 5 containing knurled wheels 6, 7 feeding the rods and the drive device therethe gun constituted by two electrodes 9, 10 secured to a "head 11 which is mounted to pivot about a spindle 12 in such manner that the electrodes can be brought in front -of or moved away from the nozzle 8. The head 11 is rotated by an electromagnet E (FIG. 1). The electrodes are fed with current by a high-tension transformer T 3,318,359 Patented May 9, 1967 ice through conductors T and T (FIG. 1). A flap 13 provided with a counterweight is connected to the electrodes and moves therewith about the spindle 12 either towards or away from the nozzle 8.

The gases are supplied to the metalizing gun by way of conduits, such as conduit 14 (combustible gas such as acetylene), 15 (comburent gas such as oxygen) and 16 (projecting or operating gas, such as compressed air). A conduit 17 is branch-connected to the conduit 16 supplying compressed air and carries an electrovalve V fixed to the casing 3. The electrovalve V is connected by conduit 18 to an exchanger vessel P in which the gas transmits its pressure to a liquid (for example oil). The purpose of this exchanger is to eliminate the compressibility of the gas (air) while transmitting the pressure thereof to the oil. The exchanger P fixed to the casing 3 is connected to a jack W by a conduit 19 carrying a flow-regulating device which is generally indicated by the reference letter R (FIG. 2) and comprises a restriction or throttle 20 whose cross-section is adjustable by means of a knurled screw 20a and a valve 22 which is inserted in a conduit 21 branch-connected to the conduit 19 (FIG. 1) and permits the oil to bypass the throttle 20 and return freely to the exchanger P (when the pressure of the gas drops in the latter). The jack W is mounted on the housing 4 and the piston thereof is provided with a screw-threaded rod 23 extending out of the cylinder. A return spring 24, one end of which is fixed to the end of the rod 23 whereas the other end bears against the bottom of a sleeve 25, assists the piston to return towards the bottom of the cylinder of the jack when the oil pressure is no longer applied. The return force of the spring 24 can be adjusted by means of a knurled-headed screw 26.

The screwthreaded rod 23 of the piston meshes with a gear wheel 27 keyed on the end of a spindle 28 controlling the device actuating the flow control valves 29, 30, 31 of the conduits 14, 15 and 16 respectively. This spindle is provided with conventional cam surfaces (FIG. 1) permitting a predetermined sequence of opening and closing of the valves, as will be explained hereinafter. It will be understood that a vertical displacement in either direction of the rod 23 rotates the spindle 28 in either direction.

Through the medium of a gear wheel 32 the screwthreaded rod 33 also drives another spindle 33 carrying cams 34, 35, 36 which have different profiles and are capable of actuating electric switches 37, 38, 39 respectively (FIG. 1).

The jack and its associated elements (spring sleeve, spindle 33 and switches) are advantageously located in a box B (FIG. 2).

The device comprises a sight 40 which has a photoelectrio cell 41, is fixed to the casing 3 (FIG. 2) and sights the flame issuing from the nozzle. The cell 41 is connected to the electrovalve V by a conductor 42 provided with a relay 43 (having a pneumatic time delay). This device closes the gas and oxygen valves if the flame disappears from the field of vision of the sight. The adjustable pneumatic time delay neutralizes the influence of the cell when changing a rod and when a temporary variation occurs in the brilliance of the flame not exceeding a pre-set period. Beyond this period the device renders the gun safe.

The other electrical connections of the device are shown diagrammatically in dot-dash line in FIG. 1. They comprise: a conductor 50 connected to a source of current (not shown) and to which is connected a conductor 51 provided with a normally open push-button switch 52 which is connected to the electrovalve V, and three conductors 53, 54 and 55 respectively connected to the switches 37, 38, 39; a conductor 56 connecting the electrovalve V to the other partof the switch 38 actuated by the cam 35; a conductor 57 connecting the switch 39 to 11 and to which conductor isconnected a conductor 58 leading to the motor M driving the knurled wheels 6, 7; a conductor 59 connecting the transformer T to the switch 37 actuated by the cam 34, and a conductor 60 connecting the electrovalve to the source of current to which con ductor is connected a conductor 61 leading from the electromagnet E. Branch-connected to this conductor 61 are the second conductor 62 of the motor M and the second conductor 63 supplying the, transformer T. A conductor 64 connects the electrovalve V to the device automatically feeding the rods so as to close the valve when there are no longer any rods on the plate, as explained in said copending application. the device according to the present invention could operate just as well withany type of metalizing gun regardless of the manner of feeding the rods.

The device according to the invention operates in the following manner:

Let'it be supposed thatthe metalizing gun is extinguished and the flap 13 is swung down as shown in the drawings.- By means of the push-button switch 52 having a .temporary action the electrovalve V is excited; compressed air from the conduit 16 is admitted into the exchanger P by way of the conduit 17. The oil is then conducted to the cylinder of the jack W by way of thethrottle or restriction 20 the flow through which has been adjusted by the' screw 20a. The rod 23 rises and rotates the 'spindles28 and 33. The spindle 28 in rotating first partly opens the gas fuel inlet valve 29 while simultaneously the spindle, 33 rotates the cam 34 which closesthe switch.

37 and results'in a supply of current to the transformer T which produces a spark between the electrodes 9 and ,10 I

which ignites the pilot light of the gun (the duration of the spark is controlled by the profile'of the cam 34). As

the rod 23 continues torise and the spindles 28 and 33 continue to rotate, the spindle 28 fully opens the valve 29 and at the'same time the valves 30 and 31, owing to the spindle, and thus supplies the comburent-gas andthe operating gas to the gun. During this time, the cam 35 8 of the blowpipe by a rotationof the head 11. The projection or jet thenvoper-ates normally, the flame being observed'th-rough the sight 40.

Inthe. event that a pressure drop occurs in the supply of operating gas (compressed air) which could deteriorate theequipment or result in a bad projection or jet, the oil flows from the jack: W into the exchanger P byway of the valve 22, it being assisted bythe. return spring 24,:and

4 tioned on the support of the gun or around the latter. The device is adjusted rapidly and precisely by acting on the screw 20a of the throttle 20 which causes the rod 23 of the jack to rise more or less quickly.

The various actions are perfectly co-ordinated in time owing to the profiles of the cams 34, 35 and 36 in particular and this ensures a fool-proof operation of the gun.

Although a specific embodimentof the invention has been described, many modifications and changes may be made therein without departing from the scope of the invention as defined in the appended claims.

This arrangement is optional and designed profile of .the cam surfaces carried by said Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1.' Device, for controlling the ignition and extinction of a metalizing gun including gas supply conduits supplying combustible gas, comburent gas and operating projecting gas and flow control means for controlling the flow through said gas supply conduits, said device comprising a jack, an exchanger, means connecting the exchanger to the gas supply conduit of the projecting gas, means connecting the jack to the exchanger so that the latter supplies liquid tothe jack for actuation of the jack by the pressure of the gas in the projecting gas supply conduit,

means 'connectingthe jack to said flow control means,

pressure of the gas supplied to the exchanger will cause the igniting means to ignite the gun and upon a drop in the pressure of the gas supplied to the exchanger below a given value will cause the igniting meansto extinguish the gun;

2. Device for controlling the ignition and extinction of a metalizing gun including gas supply conduits supplying combustible gas, comburent gas and operating projecting gas and flow control means for controlling the flow through said gas supply conduits, said device comprising a jack, a gas-oil exchanger having a gas inlet and oil outlet, a first conduit connecting the exchanger to the proiecting gas supply conduit, an electrovalve inserted in the first conduit, the jack having a piston and a cylinder, a second conduit connecting the cylinder to the oil outlet of ,theexchanger so that the jack is actuated by the pressure of the gas in the projecting gas supply conduit, regulating means inserted in the second conduit for regulating the supply of oil to the jack cylinder, a branch connection in the second conduit permitting the oil to return from the jack to the exchanger and by-pass the regulating means, the piston being connected to said flow control means to permit said gas supply conduits to supply the gases to the metalizing gun when the jack is actuated by said pressure of the gas, means for igniting the gun, means connecting the gun igniting means to the jack so the jack responsive to the pressure of the gas supplied tothe V exchanger will cause the igniting means to ignite the gun therod 23 very rapidly returns to its lower position and V rotates the spindles '28 and which are returnedto their starting, positions and this stops the gun and causes the returnv of theflap 13 in front of the nozzle 8,-thereby protectingjthe objectsubmittedto the treatmentfirom abtive functionwhen igniting. However, this fiapcould befo'mitted if desired. Ifsomething unusual occurs in the flame owing ,to an imperfect feed of rods or to an imsight 40 transmits thesignal to the relay 43 whichcloses of-the jack .W.

fTherdevice. according to the invention can beadapted rapidly and without difiiculty to any conventional metalizthe flow control means to extinguish the gun, a source of normal projections which occur when the gun is extine guished. The flap moreover performs the same protecperfect supply of fuel or comburent gas, the cell 41 of the.

and upon a drop in the pressure of the gas supplied to the exchanger below a given value will cause means including electric current, conductors connecting the sourceto the gun igniting means and to the electrov-alve, and a setof "switches inserted in said conductors.

3. Device as claimed inlclaim 2, comprising a screw 7 threaded rod connected to the piston, a spindle connected two spindles.

. the electrovalve V and thus prevents the supply of gas to the'exchanger. P and stops the gun through the medium 4. Device as claimed 'in claim 3, wherein the actuating spindle comprises cams cooperating with the switches, the profile of the cams being such as to co-ordinate in time the various operational phases of the device.

5.'Device as claimed in claim 3, wherein the set of switches isactuated by three cams.

7. Device as claimed in claim 6, wherein said branch connection includes a valve which opens when the oil pressure drops in the exchanger below said given value.

8. Device as claimed in claim 7, comprising a spring for accelerating the return of the jack to its inoperative position when the oil pressure drops below said given value.

9. Device as claimed in claim 2, further comprising a photoelectric device located in the neighborhood of the flame of the gun and means connecting the photoelectric device to the electrovalve so as to close the electrovalve when said flame operates in an abnormal manner.

10. Device as claimed in claim 2, wherein the igniting means comprise two electrodes and a transformer connected to the electrodes, one of said switches controlling the transformer.

11. Device as claimed in claim 10, wherein the electrodes are movable away from the flame of the metalizing gun after ignition thereof and into position for ignition upon extinction of the flame.

12. Device as claimed in claim 10, further comprising a flap connected to the electrodes for protecting the object intended to receive the projection from the metalizing gun when igniting and extinguishing the latter.

References Cited by the Examiner UNITED STATES PATENTS 2,382,483 8/1945 Holden 15828 X 2,505,596 4/1950 Weiler 158--28 FREDERICK KETTERER, Primary Examiner. 

1. DEVICE FOR CONTROLLING THE IGNITION AND EXTINCTION OF A METALIZING GUN INCLUDING GAS SUPPLY CONDUITS SUPPLYING COMBUSTIBLE GAS, COMBURENT GAS AND OPERATING PROJECTING GAS AND FLOW CONTROL MEANS FOR CONTROLLING THE FLOW THROUGH SAID GAS SUPPLY CONDUITS, SAID DEVICE COMPRISING A JACK, AN EXCHANGER, MEANS CONNECTING THE EXCHANGER TO THE GAS SUPPLY CONDUIT OF THE PROJECTING GAS, MEANS CONNECTING THE JACK TO THE EXCHANGER SO THAT THE LATTER SUPPLIES LIQUID TO THE JACK FOR ACTUATION OF THE JACK BY THE PRESSURE OF THE GAS IN THE PROJECTING GAS SUPPLY CONDUIT, MEANS CONNECTING THE JACK TO SAID FLOW CONTROL MEANS, MEANS FOR IGNITING THE GUN, MEANS CONNECTING THE GUN IGNITING MEANS TO THE JACK, SO THAT THE JACK RESPONSIVE TO THE PRESSURE OF THE GAS SUPPLIED TO THE EXCHANGER WILL CAUSE THE IGNITING MEANS TO IGNITE THE GUN AND UPON A DROP IN THE PRESSURE OF THE GAS SUPPLIED TO THE EXCHANGER BELOW A GIVEN VALUE WILL CAUSE THE IGNITING MEANS TO EXTINGUISH THE GUN. 